A multi-targeted, cross platform and easy to use Captcha project for using in both of DotNetCore and NetFramework
There is how to use in View:
@using NetCore.Captcha
...
@Html.MathCaptcha("Refresh", "", "Enter the captcha result here")
And, how to validate in controller's action:
[NetCore.Captcha.Validation.CaptchaActionValidator("The entered captcha is not valid")]